Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/07/19

Area Forecast Discussion
National Weather Service Bismarck ND
912 PM CDT Sat Apr 6 2019 .UPDATE... Issued at 910 PM CDT Sat Apr 6 2019 Dense fog has spread further west this evening, with webcam and surface weather observations showing dense fog across most of central North Dakota and parts of northwest North Dakota. Therefore, the Dense Fog Advisory has been expanded to include all of central North Dakota, and portions of northwest North Dakota. UPDATE Issued at 846 PM CDT Sat Apr 6 2019 Dense fog has returned across portions of north central North Dakota this evening. Visibilities of 1/4 mile or less are being reported. The latest CAM model guidance has dense fog remaining through the night. Therefore, the Dense Fog Advisory has been expanded to include Rolette and Pierce counties. UPDATE Issued at 525 PM CDT Sat Apr 6 2019 Observed temperatures across south central North Dakota have been about 5 to 10 degrees warmer than the forecast highs for today. The latest observations were blended in to adjust the forecast highs. The rest of the forecast remains well on track. Used the latest iteration of the RAP13 to populate the probability of fog this evening through tomorrow morning, which did not change the previous fog forecast by much. Still monitoring southwest North Dakota for the possible development of convection this evening as a warm front pushes through. CAM model guidance has been overdoing thunderstorm development thus far, as convection has yet to be observed across the southwest. && .SHORT TERM...(This afternoon through Sunday) Issued at 254 PM CDT Sat Apr 6 2019 A very moist boundary layer with easterly upslope flow has sustained fog, dense at times, across much of the state into this afternoon. The fog and low clouds have started to erode in far southwest North Dakota, where low-level flow is beginning to turn westerly. The expectation is for the fog and low stratus to persist where flow remains easterly. Winds will begin switching to westerly from west to east overnight as a surface trough moves through. The Dense Fog Advisory is scheduled to remain in effect for counties east of the Missouri River and south of Highway 2 until 10 AM CDT Sunday. Scattered showers tied to a mid-level disturbance continue across northwest into far north central North Dakota this afternoon. Further development tied to this wave cannot be ruled out farther south. Off to the west, isolated to scattered showers and thunderstorms are forecast to develop by early evening along the aforementioned surface trough across far western North Dakota. Forcing for ascent may be aided by frontogenetical forcing resultant from strong diurnal heating to the west of the surface trough and low-level clouds. Multiple runs of the RAP have indicated the potential for up to 1000 J/kg of CAPE over southwest North Dakota. Deep layer shear may approach 30 kts, but this is in part due to low- level flow being relatively weak. Given cold temperatures aloft, would not be surprised to see small hail with any storm that develops. This convection should dissipate overnight as it moves eastward into more stable air. Additional showers and isolated storms may develop back over southwest North Dakota overnight as a mid-level shortwave moves through. Behind the mid-level shortwave, skies should clear with increasing westerly winds on Sunday. Will need to monitor fire weather conditions across western North Dakota Sunday afternoon as highs reach well into the 60s and winds gust near 35 mph. .LONG TERM...(Sunday night through Saturday) Issued at 254 PM CDT Sat Apr 6 2019 A mid-level disturbance will bring a slight chance of rain across the state Sunday night into Monday morning, with upper-level ridging building in behind into Tuesday. Temperatures will remain above normal Monday. A strong low pressure system is forecast to move off the Rockies into the Central Plains mid week. While the existence of this storm has been consistent in guidance, its track and strength have greatly varied from model-to-model and run-to-run. Long-range ensembles continue to show significant spread. If this storm system takes a more southerly track (12Z ECMWF), much of North Dakota could remain dry. If it takes a more northerly track (12Z GFS), impactful winter weather cannot be ruled out across southern North Dakota. Regardless of the storm track, temperatures are looking to trend below normal mid to late week. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 654 PM CDT Sat Apr 6 2019 Fog will continue to affect KBIS, KMOT, and KJMS this evening through mid-morning tomorrow. The fog will be dense at times, falling to 1/4 mile or less. In addition, a stray rain shower or thunderstorm is possible tonight. Any shower or thunderstorm looks to be isolated and short-lived. Fog and low clouds will gradually push eastward tomorrow morning, giving way to mostly sunny skies and gusty winds for the afternoon hours. && .BIS WATCHES/WARNINGS/ADVISORIES... Dense Fog Advisory until 10 AM CDT /9 AM MDT/ Sunday for NDZ002>005-010>013-019>023-025-034>037-042-045>048-050-051. && $$ UPDATE...TK SHORT TERM...Hollan LONG TERM...Hollan AVIATION...TK
Area Forecast Discussion
National Weather Service Columbia SC
815 PM EDT Sat Apr 6 2019 .SYNOPSIS... A warm front will lift northward over the forecast area Sunday bringing a chance for showers and thunderstorms. A low pressure system will then move across the Deep South early next week resulting in numerous showers and thunderstorms Monday and Tuesday. Dry weather is expected Wednesday and Thursday with the next frontal system approaching the area late in the week. Temperatures near or above normal are expected over the next 7 days. && .NEAR TERM /UNTIL 7 AM SUNDAY MORNING/... Showers in the southern Midlands and CSRA have moved east of the area or dissipated with the frontal boundary remaining south of the area. Overnight the frontal boundary will slowly move northward with the main concern being a large thunderstorm complex currently in MS. The thunderstorms are expected to move northeastward and slowly weaken however the HRRR maintains the storms will reach the Upstate. As such have maintained a dry forecast for much of the overnight with slight chance of showers toward daybreak as the frontal boundary moves into the Midlands along with potential instability associated with convection in the Upstate. Patchy fog may develop along and north front where upper level dry air possible to enhance nocturnal cooling. Overnight lows will be in the upper 50s to low 60s. && .SHORT TERM /7 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... Sunday and Sunday night: A warm front will lift northward through the CSRA and Midlands during the day. Convection should develop along the lifting front but widespread showers are unlikely. With increasing moisture and instability through the afternoon, there will be a better chance of some thunderstorm development. 20 kt deep-layer shear values and weak to moderate instability suggest pulse-type thunderstorms or multi-cell clusters. A near saturated vertical profile and PWAT values at 1.5 inches or less limits the threat of downburst winds and heavy rain. Convective activity should diminish after loss of daytime heating but a few isolated showers will still be possible overnight. Temperatures will be above normal with max temps in the middle 70s to lower 80s, and overnight lows in the 60s. Monday and Monday night: Mid-level ridging pushes eastward allowing for warm, moist advection to develop in SW flow. Scattered convection should develop during the day in a moderately sheared environment. Outflow from convection that develops upstream may allow for a more organized thunderstorm system to push into the area late in the day or evening. This pattern supports a likely to categorical (55% or higher) chance of rain during the period. Temperatures will be warm through the day with highs around 80, and overnight lows Monday night in the 60s. && .LONG TERM /TUESDAY THROUGH SATURDAY/... An upper level low and associated surface low will move through the Southeast on Tuesday/Tuesday night. Showers and possibly thunderstorms should continue through much of Tuesday, diminishing overnight as the trough and deepest moisture moves eastward. Drier conditions return to the Southeast by midweek with above normal temperatures. The next frontal system will approach the area near the end of the long term period but appears to have limited moisture to work with at this time. Above normal temperatures are likely to continue into the weekend. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... High confidence for restrictions developing tonight and lingering into Sunday morning. Nearly stationary front across southern GA this evening will slowly lift north into SC overnight into Sunday. Guidance indicating MVFR cigs developing this evening then IFR or LIFR conditions especially after 08z as frontal boundary moves slowly north and low-level moisture increases across the region. The HRRR suggests fog may develop ahead of the front but confidence not high on development of low visibilities. A few showers are possible late tonight into Sunday as a weak upper level disturbance moves across the area. DNL/AGS...VFR conditions at 00Z lowering to MVFR this evening. Expect IFR/LIFR ceilings to develop by 08Z as warm front moves into the area. Visibility restrictions possible toward morning but confidence low. Ceilings will be slow to rise in the morning. Have indicated cigs lifting MVFR around 18Z. Scattered showers possible, but confidence too low to include attm. EXTENDED AVIATION OUTLOOK...Flight restrictions in stratus and/or fog expected at times, favoring late night and early morning time periods, through Tuesday. Widespread showers and thunderstorms late Monday afternoon and evening. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$
Area Forecast Discussion
National Weather Service Charleston SC
1045 PM EDT Sat Apr 6 2019 .SYNOPSIS... A series of fronts will affect the area through next week. High pressure will return next weekend. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... As of 1040 PM: I will issue a quick update to maintain a isolated thunderstorm over the GA waters through midnight. As of 930 PM: KCLX detected a few light showers over the upper Wando River area. Elsewhere, a cluster of showers was drifting east along the lower Altamaha River. I will update the forecast to lower PoPs to SCHC through the rest of the evening hours. Isolated showers may linger well into the late night hours. Fog is expected to become widespread across SE GA after 9Z. As of 745 PM: KCLX indicated scattered to isolated light showers to sprinkles over the SC Lowcountry. These showers should fade over the next 1-2 hours. I will update the forecast to adjust PoPs and remove the mention of TSRA over the land zones. Previous Discussion: Through early this evening: There are a few storms of interest over Long and Tattnall County, in close proximity to the stationary front, and also where we have a little better MLCAPE and SR helicity. Conditions favor strong winds, frequent lightning and heavy rains with these storms, maybe becoming strong if boundary or cell mergers occur. Otherwise, widely scattered to scattered showers and a few Georgia t-storms will occur as a mid level perturbation pulls off the lower South Carolina and southeast Georgia coast. Tonight: Convection over the forecast counties and upstream in southern Georgia will fade with the loss of heating and a short wave ridge moves overhead. However, with another perturbation to ripple through, the stationary front to transition into a warm front that slowly begins to lift north and weak isentropic ascent on the 295K surfaces, we still expect at least isolated showers to occur. The front will be situated near the southern border of the forecast zones this evening, and is currently forecast to make it near or slightly north of the Savannah River by daybreak. While cloud cover will be extensive near and north of the front, and will be a factor in the development of fog. There will be a little less coverage of these extensive clouds over Georgia and also the concern of stratus build down, plus the wet grounds. This will lead to "patchy" to "areas" of fog after 3 or 4 am, with the greatest coverage in Georgia where the lowest condensation pressure deficits are forecast. It is here where we have the highest potential for a Dense Fog Advisory, as depicted by the SREF, HRRR, RAP and CONShort guidance. Temps will be above climo, with most communities 60-63F, although some upper 50s over parts of the Charleston quad-county district. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/... Sunday: A weak front draped across the area around daybreak will lift north during the morning with a few showers anticipated mainly over Southeast South Carolina. The axis of a mid/upper lvl ridge of high pressure will then remain extended over the Southeast United States, helping temps warm into the upper 70s in northern areas to lower 80s across much of Southeast Georgia. Temps could even peak near the mid 80s near the Altamaha River well inland. Given the amount of sfc heating and low-lvl moisture in place, a slight chance to chance of showers are possible during the afternoon, especially for locations away from the coast. A few thunderstorms will also be possible during peak heating, but will likely remain sub-severe. Most convection should diminish by late evening with much of the area remaining dry during the overnight period. Lows will be mild, only dipping into the low/mid 60s. Monday: The mid/upper lvl ridge axis will slide offshore, helping setup a warm southerly flow over the Southeast United States well in advance of a low pressure system developing over the Mississippi River Valley. Cloud cover should increase throughout the day, but persistent warm air advection to the region should allow temps to peak into the lower 80s for most locations away from the immediate coast. Sfc heating and low-lvl moisture will once again support a slight chance to chance of showers during the morning, then greater coverage during the afternoon as moisture deepens and h5 shortwave energy traverses over the region. Showers appear likely during peak heating along with some thunderstorms, but overall severe weather potential remains low. Showers along with a few thunderstorms could persist during overnight hours. Lows will remain mild, ranging in the mid 60s. Tuesday: A low pressure system over the Deep South is expected to shift toward the Southeast United States during the afternoon and evening. Ahead of the system, moisture is expected to deepen with modest instability under widespread clouds. Showers are likely along with some thunderstorms, especially during the later half of the day when SBCAPE approaches 1000-1250 J/kg, PWATs peak around 1.5 inches and the right-rear quadrant of a 100 kt upper lvl jet promotes divergence aloft. The bulk of mid-lvl shortwave energy arrives late along with the sfc low nearing western zones during the evening. Low- lvl wind fields are not particularly impressive with the system, but could be sufficient for a few stronger storms capable of gusty winds before nightfall. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... A cold front will cross the area Tuesday night into Wednesday, with weak high pressure to build in its wake. Relatively quiet weather expected for Wednesday and Thursday. Next chance of rain will come late next week when another cold front impacts the area, however at this time precipitation looks to be in a diminishing state when it approaches. High pressure is then expected to return over the weekend. Temperatures generally at or above normal through the period. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... KCHS: Scattered light showers are forecast to pass near KCHS through 3Z. I will initialize the KCHS TAF with IFR ceilings, expecting ceilings to improve to MVFR by 3Z. MOS and forecast soundings indicate that ceilings will favor MVFR levels through the rest of the forecast period, limited by a lingering front over the region. KSAV: Light winds and lowering ceilings are expected tonight. The front is forecast to lift north of the terminal late tonight, becoming favorable to fog development. I will forecast MVFR fog by 8Z, with periods of dense fog possible between 8Z- 12Z. After sunrise Sunday, IFR ceilings are expected to expand across KSAV and may remain into the afternoon. The low clouds with thin and break apart late Sunday afternoon. Extended Aviation Outlook: Flight restrictions possible at times into Tuesday, mainly in and near showers and thunderstorms. && .MARINE... Tonight: Weak low pressure off the North Carolina coast will pull east as it reaches around 32N and 70W by daybreak. A cold front trailing from the low will extend into our far southern waters early, linking up with a stationary front near the Altamaha River, before it transitions into a warm front that will be situated SE to NW near the Savannah River by dawn. Winds will generally be Easterly at 5-10 kt, and once the evening sea breeze influences fade, winds will back more NE on the South Carolina waters and veer a little to the SE on the Georgia waters. Not much wave energy, mainly 2-3 ft. The risk for fog is low, although there could be a t-storm or two move into the AMZ354 waters through 7 or 8 pm. Sunday through Thursday: Marine conditions are expected to remain fairly quiet early next week outside of showers and/or thunderstorms that drift offshore. Southeast winds on Sunday will veer around to become southerly early next week. Speeds will increase up to 15-20 kt Monday evening into Monday night while seas build up to 3-4 ft, but conditions are expected to remain below small craft advisory criteria. A cold front will then cross the waters Tuesday night into Wednesday with high pressure to return in its wake on Thursday. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. MARINE...None. && $$ NEAR TERM...NED SHORT TERM... LONG TERM...ETM AVIATION...NED MARINE...
Area Forecast Discussion...UPDATED
National Weather Service Corpus Christi TX
835 PM CDT Sat Apr 6 2019 .DISCUSSION... Little to no activity churning this evening across South Texas so have trimmed POPs this evening which is the only change made to the grids. Still looks like the greatest chances for showers and thunderstorm activity is expected closer to around 06Z and beyond as a mid- level shortwave swings east out of Mexico. HRRR and TexasTech models both show this slower trend, with widespread activity more after 06Z. Cooling in the mid- levels with the shortwave will lead to steep lapse rates aloft. This combined with sufficient moisture will support elevated strong to severe storms with large hail moving out of Mexico into the Rio Grande Plains and Brush Country toward and after midnight tonight. WRF models also showing possible bowing segments with farther eastward movement of activity, suggesting strong damaging winds possible. Expecting activity to reach the Coastal Plains and Coastal Bend shortly around daybreak, with activity continuing to push into the gulf waters through the late morning hours of Sunday. && .PREV DISCUSSION... /Issued 704 PM CDT Sat Apr 6 2019/ DISCUSSION... Please the aviation discussion below for more details. AVIATION... MVFR/IFR conditions will quickly develop this evening across the Coastal Bend and Victoria area. This will include ALI, CRP, and VCT. An increasing cap and limited forcing will keep most of South TX free from organized convection this evening. Still could see one or two storms originating from Mexico get close to LRD by midnight but overall will keep the threat for thunderstorms low this evening. Upstream potent shortwave extending from the AZ/NM border southward into northern Mexico in association with a jet max will really begin to develop convection across Mexico later this evening to several hours past midnight. Excellent agreement on the various CAM guidance suggests that this cluster of storms will continue to become better organized with increasing dynamical forcing and sufficient 0-6 km bulk shear of 40 kt. Will begin the threat for thunderstorms by 07-08Z for COT and LRD and 10-12Z for ALI, CRP, and VCT. Will mention the possibility of gusty winds up to 45-50 kt given the potential for bowing segments to develop. The complex of storms will end from west to east between 11Z and 18Z as this shortwave moves through the area. Rapid improvement to VFR conditions will ensue once the heavy rain and thunderstorms pushes east of the area. PREV DISCUSSION... /Issued 425 PM CDT Sat Apr 6 2019/ SHORT TERM (Tonight through Sunday Night)... An upper level long wave trough currently draped along the Rockies southward across Mexico, is expect to continue slowly moving east. Embedded short waves will also continue to round the base of the trough and move northeast across the region tonight through Sunday. A strong short wave is expected to bring an MCS toward the Rio Grande Plains this evening. A few storms may develop ahead of this line through the evening hours, however the stronger, possibly severe, storms are expected to move into the Rio Grande Plains between around 11 PM CDT to 1 AM CDT. The system is expected to reach the coast sometime between 12Z and 15Z and exit the area by between 18Z to 21Z. A weak frontal bdry associated with this system, will be the main focus providing low level convergence for heavier rainfall/strongest storms. Models show strong diffluence aloft and an unstable airmass ahead of the bdry. The MCS/surface bdry are expected to exit the region by Sunday afternoon with drier conditions filtering into S TX. The primary threat is expected to be large hail and damaging wind. A few tornadoes may be possible as well. Models show helicity values of 200-300 developing Sunday morning as the storm system approaches the coast, thus the tornado threat may increase somewhat Sun morning. Heavy rainfall is also possible. Average amounts of 1 to 2 inches are expected with higher amounts possible. This could lead to localized flooding, especially across low lying areas. Given the fairly dry ground and expected steady movement of the system, widespread flooding is not anticipated at this time. Dry mid/upper levels and high surface dewpoints and light wind Sunday night could lead to areas of fog, possibly dense. Some lingering isolated convection may continue across the eastern portions of the CWA and over the waters beyond 21Z. LONG TERM (Monday through Saturday)... Increasing subsidence/drying Monday as the upper disturbance continues to move east. The GFS/ECMWF predict an upper ridge to develop Tuesday over the CNTRL CONUS as another upper disturbance approaches the West Coast. This upper system is expected to move across the Plains Wednesday night/Thursday, with the bulk of the associated synoptic scale lift north of the CWA. Yet, the GFS predicts an upper jet streak across the CWA/MSA Thursday. Nevertheless, will only introduce 10% POP values Thursday over portions of the CWA owing to limited moisture. The GFS/ECMWF predicts this system to lift NEWD across the Midwest/Great Lakes while yet another upper system develops across the SRN Rockies/SWRN CONUS then approaches the CWA Saturday. An upper jet streak Friday, and additional synoptic scale lift Saturday, along with increasing moisture in advance of jet/upper system, may result in the development of convection Friday/Saturday. MARINE... Showers and thunderstorms are expected to increase overnight and Sunday morning then tapering off from west to east late Sunday afternoon into Sunday night. A weak to moderate southeast flow is expected tonight then becoming east to northeast Sunday and northerly Sunday night as a weak frontal bdry moves across the region. Drying conditions Monday. An upper disturbance will move across the Plains/TX Wednesday night/Thursday, yet expect moisture over the MSA to be insufficient for precipitation. Upper level disturbances Friday and Saturday may result in at least isolated convection. Sea fog possible Saturday over the bays/nearshore waters given GFS deterministic surface dew point compared with likely SST values. However, not yet confident to forecast such. && .PRELIMINARY POINT TEMPS/POPS... Corpus Christi 70 80 64 86 62 / 70 80 10 10 0 Victoria 68 76 61 83 59 / 70 80 10 10 0 Laredo 68 84 64 90 63 / 80 60 0 0 0 Alice 68 81 63 87 61 / 80 80 10 10 0 Rockport 68 76 65 81 63 / 60 80 10 10 0 Cotulla 64 81 59 87 60 / 80 60 10 0 0 Kingsville 70 83 64 87 61 / 60 80 10 10 0 Navy Corpus 70 77 67 82 65 / 50 80 10 10 0 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ CB/85...SHORT TERM
Area Forecast Discussion
National Weather Service Dodge City KS
602 PM CDT Sat Apr 6 2019 ...Updated aviation discussion... .SHORT TERM...(This evening through Sunday) Issued at 106 PM CDT Sat Apr 6 2019 There will be a chance for thunderstorms this afternoon and early this evening, mainly east and south of Dodge City as an upper level trough lifts northeast from western Oklahoma into Central Kansas. A few strong or even severe thunderstorms later this afternoon can not be ruled out given the forecast instability 1000 to 2000 j/kg and 0-6km shear of 20 to 30 knots at 21Z but does improve to 30 to 40 knots by 00z Sunday. Currently based on the RAP the area most favorable for the stronger storms will be east of a Stafford to Ashland line. Will continue to favor hail up to the size of quarters given the weak shear at 21z. At 21z is when the best chances for storms exists in Barber and Pratt counties. By 00z Sunday the storms should be moving east of highway 281. As this upper level wave lifts northeast into central Kansas early this evening the convection east of Dodge City will end from southwest to northeast. As this area of convection begins to taper off the focus for early evening/overnight thunderstorms will then shift east/northeast into eastern Colorado and northwest Kansas near a surface boundary that will be located ahead of a weaker upper wave as it exits the central Rockies and approaches western Kansas. Late day heating along this frontal boundary and ahead of this next approaching upper wave should give rise to scattered convection after 21z Saturday just west/northwest of our county warning area but as these storms develop they will move east and approach Wakeeney, Scott City and Syracuse by or a little after 7 pm. Mainly small hail and gusty winds will once again be the main hazard from some of these stronger storms in our west/northwest early tonight. The potential exists for hail up to the size of quarters will be possible before sunset. On Sunday an area of high pressure will build into western kansas behind the surface boundary that will be moving across Oklahoma towards north Texas. Sunday will be warm and dry with highs climbing into the 70s. .LONG TERM...(Sunday night through Saturday) Issued at 106 PM CDT Sat Apr 6 2019 Dry and warm conditions still look on track for the start of the work week as an upper level ridge weakens as it moves from the Central Rockies and out into the Plains. Highs will warm into the 75 to 80 degree range on Monday with even a few lower 80s for highs being possible Tuesday. The next upper level trough is forecast by the GFS and ECMWF to cross into the Western High Plain mid week. This will bring our next decent chance for precipitation to southwest Kansas late Wednesday. In addition to the next round of precipitation to southwest Kansas some colder air is also expected to return behind a cold front. Temperatures behind this mid week cold front will easily be anywhere from 20 to 25 degrees cooler on Thursday compared to the high temperatures expected earlier in the week. Low temperatures Thursday night/Friday morning will range from the upper 20s to lower 30s. Highs Thursday are expected to be mainly in the 50s with even a few upper 40s for highs across portions of north central and west central Kansas. Temperatures will warm some Friday and early this weekend but the highs temperatures each day are expected to be mainly in the 50s to lower 60s. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 602 PM CDT Sat Apr 6 2019 Scattered showers and thunderstorms currently moving through east and northeast Colorado could impact Hays, and possibly Garden City, for a few hours this evening. Cigs and vsbys should remain VFR through tonight although there is some minor potential for MVFR conditions developing at Hays and Dodge City. By Sunday morning, winds will be shifting to the northwest across the area with gusts to around 25-30 knots possible by midday. && .PRELIMINARY POINT TEMPS/POPS... DDC 49 74 46 77 / 10 0 0 0 GCK 47 72 44 77 / 20 0 0 0 EHA 46 72 44 76 / 20 10 0 0 LBL 48 74 45 77 / 10 10 0 0 HYS 48 72 47 77 / 30 0 0 0 P28 52 76 49 80 / 10 10 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Burgert LONG TERM...Burgert AVIATION...Gerard
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
650 PM CDT Sat Apr 6 2019 .AVIATION... While a few showers remain south of AUS the bulk of the convection has moved away from the terminals. This will be the trend through the evening hours with dry weather expected through 09z along the Rio Grande and 11z along the I-35 corridor. VFR conditions now will drop overnight for the I-35 terminals through MVFR to IFR by 07z. These lower cigs will hang around until the morning round of rain moves through. As the main upper trough moves east across Texas another complex of showers and storms will form late tonight across the Rio Grande Plains. High resolution models show the complex moving eastward just south of DRT so have included only VCSH beginning around 09z there. The complex of showers and storms will approach the I-35 terminals by 11z with a mix of -SHRA and VCTS. While the focus should be moderate to heavy rainfall a few isolated thunderstorms are possible, so VCTS was used rather than prevailing TS at this point. The complex of showers and storms, along with any wrap around precipitation will move to the east by 15z at DRT and the I-35 terminals by 22z. VFR and dry conditions will prevail after that with northeast winds less than 10 knots. && .PREV DISCUSSION... /ISSUED 638 PM CDT Sat Apr 6 2019/ UPDATE... We have allowed the Tornado Watch to expire at 6 PM. An outflow boundary has pushed east into portions of Fayette, eastern Bastrop and southern Caldwell counties. The main threat with the remaining isolated storms west of the outflow boundary will be small hail through sunset. Re-trended PoPs and temps through the evening hours, with coverage of convective activity expected to remain isolated. No changes made to the PoPs and Wx overnight and into Sunday morning, with the previous forecast package indicating the potential of an organized complex of storms coming out of Mexico and across portions of the CWA. We will leave the Flash Flood Watch intact for the potential of flooding with this second round of storms Sunday. PREV DISCUSSION... /ISSUED 401 PM CDT Sat Apr 6 2019/ SHORT TERM (Tonight through Sunday Night)... There remains a small threat for severe weather and tornadoes with no significant improvements in the near storm airmass until the watch is set to expire at 6 pm. Some clearing of counties may need to be considered from the west in the next hour or two however. A tornado has not be detected or reported in our forecast area today, but a radar confirmed tornado was noted just north of Williamson County earlier this afternoon. A convergent pattern of a lifting warm front over eastern counties and a re-firing of thunderstorms along an eastward-propagating outflow boundary from western counties has resulted in locally heavy downpours of 2 to 4.5 inches over a small area of the eastern Hill Country and the eastern halves of Travis and Williamson counties. While much of the area is still waiting on the much anticipated rain pattern, the areas noted above have already become saturated to the point of resulting in some significant street flooding and some waters rising over some low water crossings. Overall, impacts have been spotty as has been the rains, However, the area between Johnson City and Taylor extending south to near San Marcos is expected to see another 1 to 3 inches of rain based on a good portion of the higher resolution model data for late tonight into midday Sunday. A few areas south of the FF watch area could see an isolated 4 inch amounts, but very little rainfall has accumulated thus far outside of the watch area. With a 90 knot upper jet streak currently diving south along the Pacific coast of Mexico, the model run to run trends are deeper and slower with the upper low, which should extend the residence time of the next round of heavy rains. Much of the HRRR runs today have shown good consistency on timing and location of what looks to be a more widespread mcs, which should cover 80 percent of the forecast area, with only areas NW of a Del Rio to Mountain Home line possibly missing out on measurable rains. The axis of heaviest rains with the next system should impact the San Antonio area from 6 am to 11 am and the Austin area from 7 am to 1 pm. This heavy rain axis should be along a N-S axis near Hwy 77 by 1 pm with decreasing chances of run-off producing rains in the early afternoon. However, the cumulative rains over the Austin metro area could lead to lingering flood impacts through as late as 3 pm. Additional rain chances are indicated into Sunday evening, but this should be mostly spotty rains associated with the elevated rap- around lifting processes from the middle and upper levels. Further wobbling and deepening of the upper low could lead to rain chances running into Monday morning, but these wrap-around rains should be much lighter or on the order of 1/4 inch or less. LONG TERM (Monday through Saturday)... The deeper trough moving over us this weekend will leave a dry regime and light northerly flow to promote good warming under sunny skies for Monday. Areas that have received over an inch of rain are likely to feel some of the effects of Monday afternoon humidities as the north winds are mostly expected to be less than 10 mph in the afternoon. Winds are expected to remain light Monday night, but will not factor in any chances for ground fog until we the rainfall totals for tonight into Sunday. Sunny and hot conditions develop under shortwave ridging aloft Tuesday into Wednesday. A few patches of brief morning clouds may develop Thursday morning with another mostly sunny and warm day forecast Thursday afternoon when vigorous upper low passes well to the north of the area. Later forecasts may need to consider warmer temperatures for Thursday afternoon as westerly mixing of winds aloft could be a factor. As that upper low ejects NEwd, another strong low digs into the SWrn US and brings possibly another good chance of rain for next weekend. && .PRELIMINARY POINT TEMPS/POPS... Austin Camp Mabry 65 75 59 83 59 / 40 60 20 10 0 Austin Bergstrom Intl Airport 65 74 59 83 58 / 50 70 20 10 0 New Braunfels Muni Airport 65 74 57 84 58 / 60 70 10 10 0 Burnet Muni Airport 63 73 57 81 57 / 30 50 20 10 0 Del Rio Intl Airport 64 84 59 88 61 / 60 20 0 0 0 Georgetown Muni Airport 64 73 59 82 57 / 30 60 30 20 0 Hondo Muni Airport 64 78 57 86 59 / 80 50 10 - 0 San Marcos Muni Airport 65 75 58 83 58 / 60 70 20 10 0 La Grange - Fayette Regional 67 74 60 82 57 / 60 90 40 20 0 San Antonio Intl Airport 65 75 58 85 60 / 70 70 10 10 0 Stinson Muni Airport 65 76 58 85 60 / 80 70 10 10 0 && .EWX WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through Sunday afternoon for Bastrop-Blanco- Caldwell-Hays-Lee-Travis-Williamson. && $$ Aviation...Treadway Short-Term/Long-Term...Runyen Public Service/Data Collection...EWilliams
Area Forecast Discussion
National Weather Service Hastings NE
637 PM CDT Sat Apr 6 2019 .SHORT TERM...(This evening through Sunday) Issued at 338 PM CDT Sat Apr 6 2019 Aloft: RAP dynamic tropopause analyses showed fairly zonal flow over the CONUS. An elongated weak trof was moving thru the Wrn USA and extended from MT-AZ. A shrtwv trof preceded it from CO-OK. This trof was lifting NE and will cross KS/NEB tonight. Meanwhile...the Wrn trof will cont E cross the CWA tomorrow AM with low-amplitude WNW flow after 17Z. Surface: A modified continental polar air mass was over the Cntrl Plns as the rgn was between two fronts. The polar front was stationary over the Nrn Plns while the subtropical front was stationary thru the Gulf Coast states to TX. A lee trof was to the W and extended from MT-NM. This trof will move E acrs the CWA tonight while part of the front over the Nrn Plns will drop S. This front will move thru tomorrow AM with very weak high pres moving over NEB/KS after 17Z. Rest of this afternoon: temps have climbed into the 70s with dwpts in the mid-upr 40s. This has resulted in modest instability with SBCAPE 500-750 J/kg. However...0-6 km shear was very weak (15-19 kt). Given that this combination will result in only weak updrafts...we`ll lower potential threats in the HWO down to a max of dime size hail and G40. Expect sct shwrs/tstms to cont blossoming this afternoon...mainly from cntrl KS into Ern NEB...where dwpts are well into the 50s. The Wrn edge of this activity will probably affect areas E of Hwy 281. Elsewhere...can`t rule out an isolated shwr and possibly some rumbles of thunder. Tonight: CAMs cont to indicate a narrow line of sct shwrs/tstms will form from CBK-MCK-BBW around 00Z. This line is then fcst to drift E into and acrs parts of the CWA. The 18Z NAM nest suggests far less shwr/tstm coverage than the 19Z HRRR. That`s why POPs are pretty low (mainly a chc). Skies will clear from the W after midnight...mainly W of Hwy 281. Used consensus of short-term guidance for lows. Sun: Clearing trend will cont E of Hwy 281 thru mid-mrng... leaving sunny skies the rest of the day. Could see a few diurnal stratocu develop. Windy...espcly thru early afternoon. NW winds will gust up to 35 mph. Used Superblend for highs with a nudge toward mdl 2m temps. 70-75F. .LONG TERM...(Sunday night through Saturday) Issued at 338 PM CDT Sat Apr 6 2019 Pattern: a major pattern change is in the offing. The global mdls and ensemble means conts to advertise a longwave trof developing over the Wrn USA. The look over the E Pac will be similar to what occurred in Feb and early Mar...with a high-over-low config between AK and HI. That means odds will favor cooler than normal temps...with a couple days of much colder than normal. Some snow will be possible as well. Aloft: Low-amplitude WNW flow will cont into Mon. Tue the ridge over the Wrn USA will arrive as a deep trof moves in off the Pac. This is the trof that will initiate the pattern change. It will advance thru the Wrn USA Tue night and induce lee cyclogenesis over CO Wed. The low will move acrs NEB Wed night into Thu. As that low lifts into the upr Midwest Fri...another low will dive down the W coast into the Desert SW. Heights will rise here as a shrtwv ridge moves over the CWA Fri-Sat...but that next low will be on our doorstep by Sat. Surface: A weak low and cool front will come out of the Nrn Rckys Sun night and cross the CWA Mon. This front will become stationary acrs from the NEB panhandle SE acrs KS Tue. The thermal gradient along this front will tighten as lee cyclogenesis occurs over CO Tue. There are minor diffs in where this low tracks acrs NEB or KS Wed that have tremendous impacts on the fcst. Interestingly...the GFS/EC tracks have flipped compared to prvs days. The GFS runs are now over NEB while the last 2 EC runs are over KS. That could make the diff btwn highs in the 70s/80s Wed or highs in the 40s over parts of the CWA. The CWA will be in the cold sector Thu as this low moves away. Weak high pres should briefly move overhead Fri and possibly linger into Sat. Temps: Much warmer than normal Mon-Tue with widespread 70s with low 80s from Cambridge-Plainville. Wed-Fri do not take our fcst verbatim. There is significant mdl uncertainty. What you are seeing is a blend of multiple mdls with vastly differing solutions. It is almost a certainty that Thu-Sat will be much colder than what we are advertising...espcly if/where any snow accumulates. Precip: We know a big/deep low will be moving thru Wed-Thu...but with all the mdl uncertainty on its future`s difficult to provide much detail that`s worth anything. For now we can provide possible scenarios: 1) There will probably be no shwr/tstm activity in the warm sector. This system will advect a significant cap/EML from the Desert SW. All of the precip with this system (at least while it`s over the Plns) will be on the cold side of the warm and cold fronts. 2) Light rain (and more likely drzl) will struggle to form over S-cntrl NEB Wed while a raging blzd will be on-going from the Sandhills back into the NEB panhandle. This area of deformation hvy snow would then move into the CWA Wed night into Thu...with blzd conds probable. This scenario would result in some parts of the CWA measuring svrl inches of snow with significant drifting and severe blowing snow. 3) Sct shwrs/tstms develop Wed eve with steady rain/snow moving in from Wrn NEB and NW KS Wed night into Thu. Most likely any rain would change to snow. Can`t rule out just snow moving in. This too could result in accumulating snow. These are preliminary thoughts and they could be significantly altered. There are probably other scenarios not mentioned. Other things we will need to watch... Wind: There is potential for high winds (sustained around 40 mph with gusts at or above 58 mph). Fire Wx: If the warmer/more N GFS scenario unfolds...can envision Red Flag Warnings being needed. We will need to check on status of fuels. Severe tstms: can`t be completely ruled out in the further N scenario...but we would still be dealing with a significant cap that could mitigate the risk of svr tstms. Needless to say...there is potential for multiple hazards with this mid-wk storm. Cont to closely monitor fcsts and be prepared to take any necessary precautions. && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Sunday) Issued at 630 PM CDT Sat Apr 6 2019 VFR conditions are expected through the period but there will be a chance for a -TSRA through much of the overnight hours...with strong northwesterly winds developing across the local area after daybreak Sunday. This evening...expect a line of showers and thunderstorms to develop west of the terminals...slowly tracking each and reaching KEAR by around 07/03Z. These should dissipate by the very late overnight hours...with skies beginning to clear behind the associated front around daybreak. Thereafter winds will increase behind the front...gusting to near 30KTS out of the northwest for much of the late morning through early afternoon hours. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ SHORT TERM...Kelley LONG TERM...Kelley AVIATION...Rossi
Area Forecast Discussion
National Weather Service Lincoln IL
815 PM CDT Sat Apr 6 2019 .UPDATE... Issued at 815 PM CDT Sat Apr 6 2019 Evening balloon sounding shows a fairly dry atmosphere over central Illinois this evening. Showers are edging into far southern Missouri, but the bulk of the convection is currently across eastern Kansas and Nebraska. Dry conditions expected to prevail over our area the remainder of the evening, with most of the rain beginning to move in after about 2 am. High-res models are generally focusing on a 3-4 hour period of showers and isolated thunderstorms as the warm front moves into the area, though the latest RAP shows a more widespread rain south of I-70 much of Sunday morning. Forecast was mainly tweaked for the latest PoP trends, with only minor updates to the temperatures over the next few hours. && .SHORT TERM...(This evening through Sunday) ISSUED AT 355 PM CDT Sat Apr 6 2019 1024 mb high pressure over the eastern Great Lakes and mid Atlantic States, was providing a nice early spring afternoon across central and southeast IL. Partly to mostly sunny skies prevailed, with scattered fair weather cumulus clouds along and east of the IL river. Southeast winds of 5-15 mph and a few gusts around 20 mph. Mild temperatures of 65-70F at mid afternoon with Flora, Lawrenceville, Paris and Pittsfield the warm spots at 70F. An upper level trof moving into the central plains will track across MO/IL during overnight, spreading showers and isolated thunderstorms ne across CWA. 12Z models continue to trend slower with arrival of this band of convection overnight, and may not reach areas ne of I-74 until daybreak. Lows overnight in the low to mid 50s, coolest along and ne of I-74. Chance of showers and isolated thunderstorms to diminish from sw to ne during mid/late Sunday morning and to get into a lull during part of the day Sunday as warm front lifts nne of CWA by late Sunday morning. Breezy sw winds along with some peaks of sunshine Sunday afternoon to warm temps into the 70-75F range. A cold front to push east into central IL late Sunday afternoon/early Sunday evening and could develop some scattered showers/thunderstorms. SPC day2 outlook continues slight risk of severe storms over southern 6 counties with marginal risk as far nw as a Winchester to Lincoln to Gibson City line. Models show 25-35 kts bulk shear, weak lift and some instability with CAPES peaking from 1000-2000 j/kg in southern CWA. This supports marginal to slight risk from 21Z/4 pm Sunday into early Sunday evening. .LONG TERM...(Sunday night through Saturday) ISSUED AT 355 PM CDT Sat Apr 6 2019 Chances of showers to linger in southeast IL overnight Sunday night and Monday morning as weak cold front then pushes toward the Ohio river valley into southeast IL. Models continue to trend warmer on Monday even behind weak front with highs mostly in the mid 70s and some guidance like MAV showing upper 70s over a few our or cities in our CWA. Winds look fairly light on Monday and ample sunshine over central IL, with partly to mostly cloudy skies near front in southeast IL and isolated light rain showers possible. Dry and mild weather prevailed Monday night thru Tue night across the area with highs Tue in the upper 60s and lower 70s, warmest in southeast IL. 12Z models have trended further north with warm air advection driven showers over areas from I-74 north later Tue night into Wed, and shifts mainly north of much of CWA Wed afternoon and wed night. Highs Wed range from lower 60s from I-74 ne and upper 60s to near 70F sw CWA and se IL. Models have gotten even stronger with a strong storm system ejecting out of central Rockies into the central plains by 18Z/Thu and bringing a cold front east across IL Thu evening. This will like bring another round of showers and some thunderstorms Thu and Thu evening. One more mild day Thu with highs in the low to mid 60s over IL river valley and 70-75F over southeast IL. A few thunderstorms could get strong late Thu afternoon into Thu evening with very strong dynamics of this storm system. Isolated light showers possible over east central IL fri morning, and getting much colder on back side of storm system. Highs Fri range form low to mid 50s over IL river valley and lower 60s in southeast IL. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 615 PM CDT Sat Apr 6 2019 VFR conditions expected to prevail through about 09Z. After that, a band of rain will move northeast, and ceilings expected to quickly deteriorate below 2,000 feet. A few hours of IFR conditions are expected Sunday morning, before ceilings slowly climb again. Southeast winds will trend more to the south/southwest early Sunday, following passage of a warm front, and increase to 10-15 knots. Late in the period, a cold front will cross central Illinois, with winds turning to the west. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Geelhart SHORT TERM...07 LONG TERM...07 AVIATION...Geelhart
Area Forecast Discussion
National Weather Service Nashville TN
842 PM CDT Sat Apr 6 2019 .UPDATE... FOR EVENING DISCUSSION. && .DISCUSSION... At update time, nothing is going on in Middle TN other than increasing cloud cover. However, we continue to watch to the southwest as showers and thunderstorms have moved from central MS into northern Alabama, towards the mid-state. Latest RAP continues to show improving conditions for thunderstorm development after midnight, with 500-1000 J/Kg CAPE and 35-40 kts of effective bulk shear pushing into Middle TN counties south of I-40. I feel this might be a little bullish based on the latest HRRR guidance showing only showers the rest of the night. Will keep a mention of thunder through 12Z, but as better dynamics aren`t expected until mid-morning Sunday, this might even be overkill. Speaking of Sunday, we`re still watching the potential for strong to severe thunderstorms across the northwest half of Middle TN. Latest guidance still suggests this could be possible as early as the mid to late morning hours, and persist into the early evening hours due to a couple different waves of activity. Strong damaging winds and hail continue to be the main concerns as 7-8 degree/km mid-level lapse rates are still being shown in forecast soundings. Needless to say, this isn`t likely to be a widespread severe event, but if you have outdoor plans tomorrow, it`ll be necessary to remain weather aware throughout the day. && .AVIATION... 00Z TAF DISCUSSION. KBNA/KMQY/KCKV/KCSV...We start the evening VFR, but an approaching swath of isentropically lifted air from the southwest will help spread showers and a few storms into Middle Tennessee later tonight and Sunday morning. The HRRR brings a convective complex across the mid state after midnight, and have timed the overnight weather using this short- range model. Look for ceilings to drop to MVFR by 12Z Sunday as winds increase from the south. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......Unger AVIATION........08
Area Forecast Discussion
National Weather Service Spokane WA
554 PM PDT Sat Apr 6 2019 .SYNOPSIS... The remainder of the weekend into Monday will be wet with the most significant rainfall occurring over southeast Washington as well as the central and southern Idaho Panhandle. Rises are expected on small streams and rivers including the Saint Joe, Coeur d`Alene, Palouse, and Grand Ronde Rivers. Precipitation is expected to decrease to showers Tuesday with unsettled and showery conditions for much of next week. && .DISCUSSION... Minor update to adjust evening POP`s and sky cover based on radar trends. Also removed the early evening slight chance of thunderstorms except for a small area between Sandpoint and Coeur d`Alene where a band of showers could produce a stray lightning strike. See previous discussion below for more forecast details. && .AVIATION... 00z TAFS: Drier air is moving into the region behind the weather system that brought rain earlier. Still a few lingering MVFR CIGS at KGEG/KSFF/KCOE but these should become VFR by 01z. The next weather system will spread rain and lowering CIGS into the region overnight into early Sunday morning before shifting to the south. MVFR conditions will be common over Eastern WA into the Idaho Panhandle with localized IFR conditions possible. JW && .PREV DISCUSSION... /issued 451 PM PDT Sat Apr 6 2019/ Tonight through Sunday night: Water vapor satellite imagery this afternoon shows a shortwave disturbance moving across eastern WA. A -28 C cold pool aloft at 500 mbs will help to destabilize the atmosphere. Convection through this evening is expected to be less widespread than what was observed yesterday afternoon as synoptic scale lift will be absent along the backside of this wave. The RUC and NAM models indicate the potential for 500 J/kg of CAPE into the late afternoon across the Palouse, but such a strong shear profile with around 70 kts of wind at 500 mbs will probably knock the tops off any convection as it tries to get going. Look for showers to die quickly through the evening. The next weather system will then quickly move up into the region along a warm front with good isentropic ascent in the warm sector. The trickiest part with this system will be snow levels in the east slopes of the northern Cascades. Some clearing this evening will allow temperatures to cool off near to or below freezing. Precipitaiton will begin overnight at the coldest time of the day, so expect some snow to fall around Plain and possibly in and around Leavenworth. This will also be the case in the Methow Valley and at Republic. Accumulating snow may be restricted to non road surfaces, but a different story for the passes including Blewett, Stevens, Loup Loup, Sherman and Washington Pass along the North Cascade Highway. I am expecting slushy accumulations over these passes with slick travel possible. Doesn`t appear to be enough snow to warrant a snow advisory but will need to be monitored. Otherwise, we are looking for widespread valley rain and mountain snow through Sunday morning. Models have trended drier in the lee of the Cascades Sunday afternoon with the cold front pushing in. Precipitation chances were dropped considerably as such. The area that stands to receive a considerable amount of rainfall would be over the southeast portion of the region. The cold front looks to get hung up from northeast OR to the southern- central ID Panhandle. Precipitaiton will continue to fall across these areas through Sunday night with between a half and three- quarters of an inch of rainfall possible for Pullman, the L-C Valley and into St. Maries and the Silver Valley. The Camas Prairie will see around an inch and a quarter and could be as much as a couple inches if the wetter GFS solution verifies. The added rainfall will result in rises to small streams and rivers. Rock slides and mud flows will be possible, especially in steeper terrain. /SVH Monday through Thursday...A fast moving upper short wave will push east across the PAC Northwest with weak ridging building only briefly over the region by late Monday into Tuesday morning. This upper short wave disturbance, however, will still have sufficient moisture to increase chances of shower activity over mostly the southeastern Washington zones along with central Panhandle region. The next upstream disturbance will split with most of the significant energy again being directly south across the Columbia Basin, L-C Valley, and Camas Prairie which should see a modest increase in PoPs across those areas. Model guidance mostly concurs with this assessment with the Canadian guidance showing less moisture transport than either the GFS or ECMWF guidance. In addition, enough of the cold core along with good upper vorticity should remain around Tuesday afternoon to destabilize the atmosphere and support late afternoon thunderstorms for the Idaho Panhandle mountains. There will be another brief break in the action late Tuesday night and early Wednesday, but another upper short wave disturbance will again possibly begin to affect the region by midday through afternoon Wednesday. Moisture associated with this wave will mostly increase the chance of POPs over the extreme eastern areas of Washington with the greater affect felt across the central Idaho Panhandle region. The result will be a chance for light showers developing across the regional mountains Wednesday and continuing to a lesser extent Thursday morning. Also, temperatures will range from the mid 50s to low 60s which will only be slightly above normal for this spring-time period. /aky Thursday through Saturday: The western two-thirds of the United States is expected to be under the influence of a longwave low pressure trough on Thursday. As one deep low brings the potential for a late season snowstorm to the Dakotas another trough moving into the Pacific Northwest will bring rain and snow showers to our region. Look for snow levels to be as low as 2500ft Thursday morning before rising into the 3500 to 4000ft range with scattered showers in the afternoon. There are model differences on the track of the incoming low Thursday, but it looks like there will be enough cold air aloft for the mention of a slight chance of thunderstorms in northeast Washington and north Idaho. A blend of the models suggests that there will be chances for lingering showers over the mountainous terrain Friday. Keep your fingers crossed that a transient upper level ridge will set up long enough into Saturday for some dry weather to start next weekend. /GKoch && .PRELIMINARY POINT TEMPS/POPS... Spokane 38 53 43 58 37 57 / 80 80 50 30 30 40 Coeur d`Alene 37 52 40 56 37 54 / 70 80 60 40 30 50 Pullman 40 53 44 55 38 51 / 90 90 90 40 40 50 Lewiston 44 62 49 62 44 57 / 70 90 80 50 40 50 Colville 35 56 34 56 30 56 / 40 80 20 30 20 20 Sandpoint 35 49 37 57 35 54 / 60 80 40 50 30 40 Kellogg 36 49 41 52 38 51 / 60 90 80 60 40 50 Moses Lake 41 60 43 63 38 63 / 90 80 50 20 20 20 Wenatchee 38 57 40 58 39 59 / 90 80 40 20 30 10 Omak 36 58 39 58 36 60 / 30 70 10 20 20 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
Area Forecast Discussion
National Weather Service Paducah KY
1001 PM CDT Sat Apr 6 2019 .UPDATE... Issued at 1001 PM CDT Sat Apr 6 2019 Made some adjustments to PoP, weather, and QPF for the rest of tonight and the daytime hours on Sunday. Added a mention of "gusty" winds to part of the WFO PAH forecast area after 3am CDT through 7 am CDT, mainly over parts of southeast Missouri and the Purchase area of west Kentucky to reflect the threat of higher wind gusts. The stronger wind gusts translate over to parts of southeast Illinois, west Kentucky, and southwest Indiana through the morning hours on Sunday. Given the broad slight risk area depicted by the Storm Prediction Center for Sunday, was not confident enough to make a distinct severe wording mention at this time at any one location with this update. Looking the the 00z/01z Sunday RAP and 18z Saturday/00z Sunday 12km NAM guidance, there is some concern that the 0-3km contribution of bulk shear (35-45 knots), localized 200-400 m2/s3 surface helicity, overturning of drier air aloft from the northwest, as well as some MUCAPE expenditure could lead to some robust rotating updrafts leading to strong thunderstorm (severe?) development in southern sections of southeast Missouri around or shortly after 12z (7 am CDT) Sunday, rapidly translating toward southeast Illinois, southwest Indiana, and northwest Kentucky between 10 am CDT to 1 pm CDT. The RAP/NAM guidance are strongly suggestive of drier air aloft descending into western sections of the WFO PAH forecast area during the afternoon hours on Sunday, limiting the depth of deep layer moisture. At this time, not confident enough to totally eliminate PoPs in this area, so kept with the trend of lowered PoPs depicted by the dayshift short term forecaster. The main potential for enhanced wind gusts will likely shift toward the Pennyrile region of west Kentucky by the middle and late afternoon hours. UPDATE Issued at 603 PM CDT Sat Apr 6 2019 For aviation section only. && .SHORT TERM...(Tonight through Monday night) Issued at 303 PM CDT Sat Apr 6 2019 Early this afternoon, high pressure was across the eastern U.S., with low pressure over the High Plains of the central U.S. An energetic s/wv aloft was lifting northeast into the central Plains, with a second wave, perhaps convectively induced over the Red River Valley region. Expect a quiet early evening. Then our focus turns to the aforementioned wave to our southwest. It is forecast to move northeast and across the region tonight. Expect some showers and a few thunderstorms, generally from 03-04z SEMO, to 08-10z up across the KEVV tristate as the activity moves northeast. After the passage of this wave, there may be a brief lull, but the models continue to show some mid level support for additional showers and storms Sunday morning. Convection, and any severe weather possibility is highly conditional Sunday. The CAM`s data gets the gist of what`s going on...the wave tonight, then a regeneration of convection Sunday morning through midday. The activity should be more focused over west KY by Sunday afternoon, possibly dropping off in coverage or ending for a time up across southern IL into southwest IN and parts of SEMO. The NAM suggests too much ongoing convection will be a hindrance to good destabilization Sunday. The GFS is more unstable and across more of the area. Tend to think without much if any capping, and the presence of mid level support, it will not take long for convection to get going again, increasing clouds and possibly limiting further destabilization. Overall, seems like a marginal severe risk, with the best chance of severe over west KY where there should be slightly better 0-3km bulk shear juxtaposed with slightly better instability. The lull will continue Sunday evening, then activity picks back up after 06z Sunday night, as a secondary southern stream H5 low heads east across the southern U.S. resulting in an uptick in moisture for showers and maybe storms over our southeast counties, primarily west KY. The chance will taper off Monday from west to east as the wave moves away from the area. It will be warm and somewhat humid through the period with little change in airmass expected, once we get in the more humid air tonight as a warm front lifts north across the area. Went with persistence, MOS and model output for temps. .LONG TERM...(Tuesday through Saturday) Issued at 303 PM CDT Sat Apr 6 2019 The primary forecast concern in the long term is the potential for showers and thunderstorms Thursday and Thursday night, in addition to windy conditions, with the approach and passage of a low pressure system and its associated cold front. Fairly good model agreement lends higher than average confidence to the forecast through Friday. Confidence drops off by next weekend with greater model variability. Starting with Tuesday morning, a ridge of high pressure is forecast to be centered along the range of the Rocky Mountains with split northern and southern stream troughs over the eastern U.S. The ridge is forecast to build east through mid week, resulting in dry weather through Thursday morning. Southerly winds will begin to pick up on Wednesday and especially Thursday as a low pressure system develops over the Central Plains and moves east towards the Mississippi Valley. Winds on Thursday will be quite strong, sustained 20 to 25 mph with gusts of 30 to 40 mph at times. The combination of forcing for ascent and increasing Gulf moisture will lead to a chance of showers by Thursday afternoon and evening. Thunderstorms will also be possible given the projected availability of surface based instability. Given the magnitude of forecast wind profiles, a few strong storms are not out of the question. Dry weather should return by Friday in the wake of the cold front. Models have shown some divergence heading into the weekend, but the 12Z ECMWF is admittedly fairly close to the GFS and CMC. Shortwave energy over the southwestern U.S. is forecast to eject east across the southern Plains, resulting in an increasing chance of showers, especially by the latter half of the weekend. At this time, the current forecast includes a small chance of showers on Saturday, mainly influenced by the faster 00Z ECMWF. Temperatures will start off warmer than normal with highs in the mid to upper 70s Tuesday through Thursday, dropping back into the 60s Friday and Saturday. Lows should rise from around 50 Tuesday night to near 60 Wednesday night, then drop back into the 40s by Friday night. && .AVIATION... Issued at 605 PM CDT Sat Apr 6 2019 Tonight, there will be a chance of showers and storms mainly after midnight, with VFR cigs possibly lowering to MVFR after 06z. The chance of showers and a few storms will continue Sunday low VFR to high MVFR cigs the rule. Brief IFR cigs and MVFR/IFR vsbys likely in heavier showers and storms, scattered across the area. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...None. MO...None. IN...None. KY...None. && $$ UPDATE...Smith SHORT TERM...08 LONG TERM...RJP
Area Forecast Discussion
National Weather Service Blacksburg VA
1125 PM EDT Sat Apr 6 2019 .SYNOPSIS... Weak ridge of high pressure will remain anchored over the Tidewater Virginia area through tonight. A low pressure system over the north-central Plains tonight will move east into the Great Lakes on Sunday then will bring a cold front through the region Tuesday. Then the next storm system from the central United States will impact the east on Friday. && .NEAR TERM /THROUGH SUNDAY/... As of 1124 PM EDT Saturday... Update to account for cooler temperatures given better radiative cooling as skies have cleared. Winds are expected to remain light east to southeast across eastern parts of the forecast area under weak ridge of high pressure. With dewpoints even higher than last night, this will again favor potential patchy mist or fog with intervals of low clouds as well. Visby progs from the GFS LAMP guidance as well as the HRRR and NAM-3km each show this fog potential well in the Piedmont and foothills areas, with more mixed signals in the New and southern Shenandoah River Valleys. Will introduce a greater fog coverage areawide which should last into early Sunday morning. Otherwise, forecast appears to be on track. Previous discussion from this afternoon... High pressure will slide east and northeast tonight into Sunday. Meanwhile, a warm front lifts northeast from the Gulf Coast states across Virginia during the day Sunday. Tonight, aside from some pockets of light rain along the Blue Ridge, look for skies to fill back in with stratus due to low level inversion. Most will be cloudy Sunday morning at dawn, with patchy fog around. Temps will be above normal by about 5 to 12 degrees, with lows in the lower to mid 50s. Sunday will be mild again. Instability appears a little more limited until later in the day after the warm front moves across due the cloud cover. Best lift and instability look to move across the TN Valley into the southern Ohio Valley. Nonetheless, expect some thunderstorms to make it toward far SW VA/southern WV and NW NC by late afternoon, with best chance/coverage of showers west of the Blue Ridge with less threat in the Piedmont. Highs to range from the mid 60 to around 70 along/west of the Blue Ridge, to lower to mid 70s in the Piedmont. Forecast confidence in temps and winds is high, but medium/average on clouds and thunderstorms. && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... As of 330 PM EDT Saturday... Sunday night into early Monday, a shortwave trough will progress eastward through the eastern Great Lakes region. Concurrently, a stronger closed low over eastern Texas will be making slow progression towards the Arklatex region. Light isolated to scattered showers are still forecast Sunday night into early Monday in association mainly with a good moisture fetch into the area, and upper level support from the northern stream shortwave trough. Once we progress into Monday night, while the moisture feed continues, upper level support will transfer to that provided by the slow moving closed low that will be near the MS/AL border around daybreak Monday. From Monday through Tuesday, the model solutions have trended with a farther south track of the southern stream upper low. For our region, this should mean that the best instability should be positioned farther south of the forecast area, but not displaced so much as to preclude any thunderstorm activity. We will continue to have very good coverage of showers during this time period, but with the best thunderstorm potential generally along and south of Route 460, with much less coverage north of this area. Temperatures during the Monday and Tuesday portion of the forecast will average about 10 degrees above normal. && .LONG TERM /TUESDAY THROUGH SATURDAY/... As of 330 PM EDT Saturday... An upper level shortwave ridge of high pressure will settle over the region Wednesday into Wednesday night. This feature, and high pressure at the surface, will provide the region with dry weather and temperatures around five to ten degrees above normal. Expect Thursday to be a day of transition. The surface ridge and surface high will be shunted eastward in response to an approaching upper level low across the Central Plains states. Flow between this departing high and approaching low will slowly veer south as Thursday progresses and increase in speed to near 30 to 40 kts at 850mb. The origins of the air being advected into the area will be from the Atlantic, just off the coast of the Carolinas. As this moisture butts up against the higher terrain of the Blue Ridge, isolated to scattered showers will be possible late in the day Thursday across parts of the Northern Mountains and Foothills of North Carolina. Thursday night we are expecting the coverage of upslope showers to advance northeastward along the crest of the Blue Ridge. Additionally, the approach of the upper level low and its associated trough will allow for isolated to scattered coverage of showers across much of the rest of the forecast area by daybreak Friday, with the best coverage across southeast West Virginia. For Friday, model guidance is in better agreement than their counterpart solutions of 24 hours prior. Confidence has increased for there to be a significant coverage of showers across the region in advance of the upper low`s associated trough axis and surface cold front. Winds at 850mb are forecast to continue increase in speed, 40 to 45 kts, and continue veering to more a southwest direction. With the GFS offering 0-1km shear of 30kts, Showalter values between -3 and -2 C, and SB-VIs as low as -3 to -2 C, and SBCAPE around 400-600 J/Kg, will continue with the mention of isolated thunderstorms for at least the entire forecast area around mid-day. By the late afternoon, additional storms more likely will be focus across the southeastern portion of the area and perhaps increase in coverage to scattered, before trending to isolated again by sunset. Friday night into Saturday, model guidance has trended slower with the departure of the cold front and lingering isolated showers in its wake. Will reflect this with a slight chance of showers across primarily the southeastern sections of the area during this time period. Temperatures across the area Thursday into Friday will continue to be around five to ten degrees above normal. In the wake of the cold front, readings on Saturday will be more in line with values around five degrees above normal. Confidence in this portion of the forecast is moderate. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... As of 750 PM EDT Saturday... TAF sites will start the period with VFR conditions. However as high pressure continues to slide off to our east, southeasterly winds will pool low level moisture along and east of the Blue Ridge, developing IFR CIGs as well as some fog overnight. Flight conditions will trend upward a bit Sunday as a warm front moves up from the southwest and brings some showers and possibly thunderstorms to the Appalachians. The best forcing will slide by to our northwest and keep the best chance of showers/thunder west of the Blue Ridge, so will confine mention thunder to KBLF and KLWB. EXTENDED AVIATION DISCUSSION... MVFR/IFR conditions are possible with scattered showers and isolated thunderstorms through Tuesday. Drier weather and VFR ceilings and visibilities are expected Wednesday into Wednesday night. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...AL/AMS NEAR TERM...AL/WP SHORT TERM...DS LONG TERM...DS AVIATION...MBS EQUIPMENT...AMS
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
749 PM EDT Sat Apr 6 2019 .UPDATE... We saw a couple of moderate storms this afternoon along the Nature Coast and inland areas of Polk County with some gusty winds around 25 knots and dime sized hail reported. These were short lived and did not meet any severe weather criteria. The radar is quieting down this evening with only a couple of storms over the northern part of Polk County. HRRR guidance has all storm activity dying down over the next couple of hours with a quiet night expected. Temperatures topped out in the middle 80`s for most of the area which was around 5-7 degrees above average. A warm night is expected tonight with another hot day on tap for tomorrow. Adjusted the POPs down for tonight based on latest radar imagery and model guidance. No other changes needed at this time. && .AVIATION... VFR conditions are expected to hold through the period. Winds will be light and variable overnight, then increasing east-southeast at 10 knots or less during the day on Sunday. No other aviation impacts expected. && .MARINE... Some sea fog possible tonight north of Tarpon Springs. Otherwise high pressure north of the waters will keep predominantly east- southeast flow over the waters through the first half of Monday, then winds turn onshore for the rest of the period. No headlines expected as winds remain 15 knots or less. Periods of showers and thunderstorms possible Monday and Tuesday, followed by improving conditions on Wednesday. && .Preliminary Point Temps/PoPs... TPA 71 87 72 85 / 10 10 0 30 FMY 70 89 70 88 / 0 30 0 20 GIF 69 89 70 89 / 20 0 0 50 SRQ 68 85 69 84 / 10 10 0 20 BKV 64 88 66 87 / 10 10 0 40 SPG 72 86 73 85 / 10 10 0 30 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...None. Gulf waters...None. && $$ UPDATE/AVIATION/MARINE...74/Wynn DECISION SUPPORT...25/Davis